Dynamics of end-pulled polymer translocation through a nanopore

Abstract

We consider the translocation dynamics of a polymer chain forced through a nanopore by an external force on its head monomer on the trans side. For a proper theoretical treatment we generalize the iso-flux tension propagation (IFTP) theory to include friction arising from the trans side subchain. The theory reveals a complicated scenario of multiple scaling regimes depending on the configurations of the cis and the trans side subchains. In the limit of high driving forces f such that the trans subchain is strongly stretched, the theory is in excellent agreement with molecular dynamics simulations and allows an exact analytic solution for the scaling of the translocation time τ as a function of the chain length N0 and f . In this regime the asymptotic scaling exponents for τ ∼ N α 0 f β are α = 2, and β = −1. The theory reveals significant correction-to-scaling terms arising from the cis side subchain and pore friction, which lead to a very slow approach to α = 2 from below as a function of increasing N0.

Theory of pore-driven and end-pulled polymer translocation dynamics through a nanopore: an overview

“…The orange solid lines come from the IFTP theory when we solve the equations of motion with a combination of all the three SSC, SFC and TRC regimes (a full description for the SFC and TRC regimes can be found in Ref. [84]). The equations are solved in the SSC, or SFC or TRC regime iff 0 N 0 −s, or 1 f 0 < N 0 −s orf 0 1, respectively.f 0 has been introduced in Eq.…”

Force spectroscopy analysis in polymer translocation

“…Motivated by the results of different experiments with passive pores [17][18][19], many studies of translocation have been performed, mainly under constant forces, either pore-driven or, less commonly, end-pulled [20]. The role of active nanopores, with time dependent mechanisms assisting the translocation, has been only more recently * Electronic address: afiascon@unizar.es considered.…”

An improvement of the sequential algorithm for modeling the chain-like-bodies motion

“…The translocation process is investigated via a variety of experiments [1,8] and theories [1,8,9]. However, because of a lot of limitations of experimental studies, this process is also widely studied by simulation experiments [10][11][12]. It should be mentioned that the translocation of the CLB through the membrane can be done with the presence of an external driving force [1,2,11] or without it [8,13].…”

“…However, because of a lot of limitations of experimental studies, this process is also widely studied by simulation experiments [10][11][12]. It should be mentioned that the translocation of the CLB through the membrane can be done with the presence of an external driving force [1,2,11] or without it [8,13]. Mechanisms which are used as the driving force are e.g.…”

“…An improvement of the sequential algorithm for modeling the chain-like-bodies motion11 the new position of c 5 presented inFigure 7bis more probable than position presented inFigure 7a.…”